Preparation Place mushrooms in large bowl. Pour 3 cups boiling water over; let soak until mushrooms soften, at least 25 minutes and up to 4 hours. Drain. Cut off stems and discard; finely chop caps. Dissolve cornstarch in 2 tablespoons vegetable broth in 2-cup measuring cup. Stir in remaining broth, soy sauce, vinegar, sugar, and salt. Heat oil in heavy large wok or nonstick skillet over high heat until very hot. Add mushrooms; stir-fry until browned, about 3 minutes. Add leek; stir-fry until beginning to brown, about 1 minute. Add black beans, ginger, garlic, chili-garlic sauce, and peppercorns; stir-fry 30 seconds. Stir cornstarch mixture to blend, then stir into vegetable mixture. Add tofu; toss gently to coat with sauce. Reduce heat to low, cover, and simmer until sauce thickens slightly, about 4 minutes. Spoon tofu mixture into serving bowl. Garnish with cilantro and serve. *Available at Asian markets and specialty foods stores and in the Asian foods section of some supermarkets.
Preparation Place mushrooms in large bowl. Pour 3 cups boiling water over; let soak until mushrooms soften, at least 25 minutes and up to 4 hours. Drain. Cut off stems and discard; finely chop caps. Dissolve cornstarch in 2 tablespoons vegetable broth in 2-cup measuring cup. Stir in remaining broth, soy sauce, vinegar, sugar, and salt. Heat oil in heavy large wok or nonstick skillet over high heat until very hot. Add mushrooms; stir-fry until browned, about 3 minutes. Add leek; stir-fry until beginning to brown, about 1 minute. Add black beans, ginger, garlic, chili-garlic sauce, and peppercorns; stir-fry 30 seconds. Stir cornstarch mixture to blend, then stir into vegetable mixture. Add tofu; toss gently to coat with sauce. Reduce heat to low, cover, and simmer until sauce thickens slightly, about 4 minutes. Spoon tofu mixture into serving bowl. Garnish with cilantro and serve. *Available at Asian markets and specialty foods stores and in the Asian foods section of some supermarkets.